ATI’s Digital Audio driver reduces Radeon’s 3D performance?

UPDATE June 22, 2009 15:35 GMT – We spoke with key personel at AMD over this situation and the answer we got from AMD was the following: The probability for this to happen is around 2.3%. Long story short, if there is a “performance shortfall” detected on the system, that is caused by the presence of eventual 3rd party audio driver such as ones made by RealTek. The solution is simple:

• Uninstall Audio driver for the on-board sound chip
• Reinstall Catalyst drivers
• Reinstall Audio diver for the on-board sound chip

That’s it.

ORIGINAL STORY

We all know that ATI was the first company to implement HDMI support with a digital HD sound hardware built-in inside the GPUs ever since X1300 and its agreement with Creative Labs [but X1K was found not to support HDCP, hence the recent class action settlement].

Radeon HD 2000 series fixed the HDCP issue and things went back to normal, but now Hardware-Infos claim that you actually lose a little bit of 3D performance if you drive the audio through the graphics card. While in theory this should not happen – as HD audio is just passing through the PCI express bus and being synced with the picture, independent testing is now showing that Radeon 4800 series suffers from a small performance drop regardless of HDMI being an active connection or not.

Benjamin discovered that disabling the “ATI Function Driver for High Definition Audio” in Device Manager brings a small performance boost.

In games such as Crysis Warhead, Far Cry 2, GRAW 2, GTA IV, Tom Clancy HAWX and Stalker: Clear Sky in 1920×1200, with 4x AntiAliasing and 16x Anisotropic Filtering, disabling the “ATI Function Driver for High Definition Audio” brought anywhere between two and five percent. Most of applications saw a difference between 2-3 percent [inside the margin of error], but five percent is a tangible difference.

Original Author: Theo Valich